Unleashing the Dragon by Noah Harris

Everyone is trying to find their own place in the world, but the courage to be who you really are is more complicated than you might think.
Coast Guard pilot Barry has just arrived home after being listed as missing-in-action and believed dead. His experiences have left him profoundly changed but he has come back to the real world with more than just a story to tell.

Joining him on his return to civilization is Xanathen, the striking island native whose muscular frame and physical prowess not only helped save Barry’s life but also forever changed who he was and how he saw the world.
As they work to navigate their new lives together and help one another grow, they are faced with numerous obstacles neither one could have expected. When a mysterious new stranger enters their lives with a secret of his own, they must decide how strong the bond they share is between them.